The Chesed Siyum
The popular idea of making a siyum mishnayos for someone who has passed away, in which random people take on masechtos in order that their learning should benefit the deceased, is of extremely recent origin and is theologically very problematic. As the classical Torah authorities point out, there is simply no mechanism to credit other people with mitzvos which had nothing to do with them. You can honor anyone's memory in this world with any kind of good deed, but your actions are only actually a credit to them (from both our perspective and God's perspective) if they actually influenced your actions, such as if they were your parent, teacher or exerted some sort of formative influence. (See an additional source on this, which I added at the end of this post.)
Yet the idea that you can give anyone the merit of your Torah learning has become increasingly popular. One reason is that some people have found this easy to commercialize. Once you posit that anyone can learn Torah to benefit anyone else, then you can manipulate people into giving you money so that you (or the people in your kollel) will allegedly benefit their loved one. But in reality, the deceased is not getting any credit for this Torah learning. And it's often not even a particularly suitable or meaningful way of honoring their memory.
Fred Distenfeld z"lIt is therefore very gratifying to see that my friend Gershon Distenfeld has come up with a terrific project to honor the memory of his father, Fred Distenfeld z"l: a "Chesed Siyum." This involves reaching out and encouraging family and friends, and anyone else who wants to participate in chesed on a community level, to sign up and pledge to perform acts of chesed in memory of Fred Distenfeld.
The Chesed Siyum differs from a Mishnayos Siyum in three key ways:
First, there is the obvious difference in that the mitzvah being done is one that helps other people. This is as opposed to learning Torah, which only benefits oneself; it does not benefit either the deceased (except when they are an ancestor/teacher) or society at large (at least, according to classical Jewish thought rather than recent mystical innovations).
Second is that while learning Mishnayos would be a meaningful way to honor the memory of, say, someone who wrote a commentary on the Mishnah, it's not a particularly meaningful way to honor the memory of most people. Fred Distenfeld had an amazing reputation as a baal chesed, and so doing chesed is actually a meaningful way to honor his memory.
Third is that many of those taking on this mitzvah are doing so because they are inspired by the sort of person that Fred Distenfeld was (even if they did not know him personally, and only from reports). Thus, the chesed being done can be attributed to his influence; it is indeed a credit, a zechus, for him.
See the article about the Chesed Siyum at https://www.jewishlinknj.com/community-news/bergen/24679-join-the-family-of-fred-distenfeld-for-a-chesed-siyum-in-his-memory. And you can sign up for the Chesed Siyum at https://tinyurl.com/yaygv3cq.
UPDATE: See this additional 16th-century source which states that mitzvos are only a benefit to the parent because the parent is the actual cause of this person:
שו"ת בנימין זאב סימן רבאין זכות הקרובים מועיל אלא זכות הבן לאב כההיא דאמרינן ברא מזכי אבא ולא אבא מזכי ברא... זכות ומצוה הוא לאב כשאחד מיוצאי חלציו יקדיש ה' הגדול הנכבד והנורא לעיני כל העדה... כיון שעצם מעצמיו ובשר מבשרו הוא גורם היות ה' הגדול והנורא מתקדש שמו ברבים וזה אצלי טעם קדיש לבן ומזה הטעם ברא מזכי אבא מפני שהבן הוא האב וכל מצות הבן ומעשיו הטובים ממנו משתלשלים ויורדים אבל זכות ומצות של שאר קרובי' אינו מועי' כלל לנפש המת דמאי זה טעם יועיל זכות ראובן לשמעון ולוי אחים ומצותיו מה יעשו להם